Re: Z39.50 Searching

Am Mittwoch, 15. September 2004 20:29 schrieb Slavko Manojlovich 
<slavko@mun.ca> [RE: Z39.50 Searching]:

> I thought that structure = wordlist was deprecated because it supported
> default behaviour vis a vis the application operators on the server side.
> Some servers default to "AND" and other servers default to "SAME FIELD".
> Ideally, you would send this search as structure = 2 with the "AND"
> operator.

Seems to be bad luck for me: I was hoping I could tell the server implementors 
to change their serversī behaviour, but if there is no exact definition of 
how a server should react to such queries my negotiating position seems quite 
weak.

> Quoting "LeVan,Ralph" <levan@oclc.org>:
> > It's not obvious to me why you get these different results. 

Neither to me ;-)
In my opinion the "word list" query should yield all hits as there is attr 3=3 
(Position = any pos. in field) which IMHO should apply to all words of the 
word list separately. And there should be no hidden logic about differrent 
fields beneath the index and the occurence of all words in one of these. But 
after all thatīs just an opinion....

> > An experiment would be to repeat the search, omitting attribute types 2,
> > 3 and 5, since they were also omitted from the ANDed search.

That still gives me no hits.

> > If you still get different results, I'd contact the database provider.

I contacted one of the developers of that system and he told me their system 
would conform to the standard because it assumes that searching with a word 
list implies "all words from one field/subfield" (regardles of the value of 
the Structure attrib in the query).
If Slavko is right, thatīs not entirely true but then neither is my opinion.

Iīm still wondering, however, what is really meant by the terms 
"field"/"subfield"?
Since Z39.50 provides an abstraction layer for searching and the record 
syntaxes are decoupled from the search indices: how am I supposed to find out 
what fields and subfields there are?
Could anyone provide me with a definition of these terms or point me to a 
discussion of this topic?

Still wondering
Heiko
-- 
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Received on Thursday, 16 September 2004 16:37:01 UTC